Last year just before Christmas I bought one of my daughters a £50 gift voucher from Tesco to pay towards Christmas dinner and for some reason I made a note of the number on it.
I've just asked her if she would like me to do this again for her this Christmas and she let slip accidently that she lost it and so never used it.
Just went on their gift card page and put in the number and it's showing a balance still of £50.
If I were to phone them to explain the situation, do you think there is anything they might be able to do about it?